1. Technical Field
The present disclosure relates to an electrical signal transmission module, a method of transmitting electrical signals, and an electrical inspection apparatus. More particularly, to a module and a method for transmitting electrical signals to inspect a semiconductor device and an electrical inspection apparatus having the module.
2. Discussion of the Related Art
Semiconductor devices are manufactured by a fabrication process for forming electric circuits including electric elements on a semiconductor substrate such as a silicon wafer. An electrical die sorting (EDS) process is used for inspecting electrical properties of chips formed by the fabrication process, and a packaging process is used for sealing the chips with resin such as epoxy and for sorting the chips.
The EDS process applies an electrical signal to the chip formed on the silicon wafer and obtains an output signal from the chip to determine whether the chip is defective. The EDS process is performed by an electrical inspection apparatus including probes that directly make contact with pads of the chip.
As the operation speeds of semiconductor devices increase to higher than about 1 GHz, the electrical inspection apparatus is required to operate at a high speed in order to accurately inspect the semiconductor device.
FIG. 1 is a block diagram illustrating a conventional electrical inspection apparatus.
Referring to FIG. 1, the electrical inspection apparatus 1 includes a test header 10, a first connector 20, a performance substrate 30, a second connector 40, a main printed circuit board (PCB) 50, an elastic interconnector 60, a subsidiary PCB 70, and a probe 80.
An electrical test signal from a tester (not illustrated) is input into a semiconductor device through the test header 10 to the probe 80, and then an electrical signal generated by an internal operation of the semiconductor device is input into the tester through the probe 70 to the test header 10. The tester analyses the electrical signal to inspect the semiconductor device.
In order to accurately inspect the semiconductor device, the electrical inspection apparatus must transmit the input/output (I/O) electrical signal to/from the tester without loss or distortion of the electrical signal. The electrical inspection apparatus including the PCB may accurately inspect a semiconductor device having an operation speed of less than about 500 MHz without loss of the electrical signal or loss of power.
However, when the operation speed of the semiconductor device is higher than about 1 GHz, because the PCB includes glass fiber having an epoxy resin, loss of amplitude and distortion of the waveform of the electrical signal may occur. Further, the loss of the amplitude and the distortion of the waveform of the electrical signal may occur due to crosstalk between electrical signal lines of the PCB. Accordingly, the electrical inspection apparatus may not accurately inspect semiconductor devices having an operation speed of higher than about 1 GHz.